Hello,

A part of my application currently have a supervisor hierarchy that looks something like this:

supex541×441 7.2 KB

As you can see, I have a Manager Genserver and a Childs Supervisor that will contain a lot of children’s (this is a normal supervisor for now, but maybe in the future I would want to start the children on demand, so that can be changed to a Dynamic Supervisor in the future I guess).

My question is regarding the Manager Genserver communication with the children’s. Basically Manager Genserver needs to send broadcast messages to all the children’s, this can happen very frequently (like multiple times a second), so I have a performance concern.

So, what kind of communication strategy should I use in this case? I’m kinda new with OTP, so I’m not 100% sure and are contemplating the following solutions:

1. Create a function inside Childs Supervisor that will iterate and do a GenServer.call to all it’s children. Not sure if this is efficient or will bottleneck all the communication if one children blocks the call for some reason;

2. Send a message from each Child to the Manager GenServer with it’s PID, store it in a list and send GenServer.call iterating through it;

3. Use a PubSub system like Phoenix.PubSub. This seems like a good solution, but as far as I know the Phoenix.PubSub is global and used more for a distributed case. I’m not sure if using it would be over-engineering and maybe be a bottleneck;

4. Use the Registry. this seems like another good solution too but I only saw examples of global (but local to the beam node) examples of Registry, in my case I only want to handle communication from Manager Genserver to all the Childs, is it possible to create maybe a local Registry for Parent Supervisor?

Any help would be much appreciated.

Thanks a lot!